An online charging system (OCS) is a system that performs charging interaction in real time based on service usage. The OCS mainly refers to a charging system that participates in communication process control and that can resolve problems such as user real-time credit control, usage of a prepaid data service, and real-time charging for a value-added service.
User equipment accesses the OCS by using a gateway. For security and other considerations, a gateway device is further decoupled into a control plane entity of the gateway device and a user plane entity of the gateway device. The control plane entity of the gateway device implements user access control, charging policy control, charging data record management, and the like. The user plane entity of the gateway device implements service data forwarding, and executes a control and charging policy and the like delivered by the control plane entity of the gateway device.
However, after a gateway device is decoupled into a control plane entity of the gateway device and a user plane entity of the gateway device, there exists a technical problem that a charging path is extremely long and a charging delay is large in some approaches.